My new GTR have battery sag issues. Anyone else had problems?

I purchased a bamboo gtr and have been riding for a few weeks. The other day i had been on a sk8 about 25km and board was at 47%. On way home i went up a small hill and was at 0% with remote vibrating.

Had same problem today, was at 61% at bottom of small hill. Then 0%

Has anybody else had similar problems?

 

I just got my new Carbon GTR and have only ridden it once. No issues yet. My previous Bamboo GTX had battery sag issues after about 2.5 years of riding. It still runs well but I did start noticing that. My choice was a battery upgrade or a new board. I chose the new GTR board because of all the good things I had read about it. Time will tell. I would definitely reach out to Evolve. That doesn’t sound normal for a board that is only a few weeks old. Good luck and let us know how Evolve responds to this issue.

 

Hey Guys

It sounds as though the BMS may not be calibrated properly. You will need to run the board completely dead, until it turns off. NOT just 0%, it needs to be run til it turns off, under normal load.
Once it has turned off, charge it to full in one go and test again. This should recalibrate the BMS SOC calibration.
If you are still having concerns, contact your local Evolve for support.
Cheers, Nick.

 

I was worried about this as the GTR batteries are better but still not great...

 

Hi
There's no issue with the battery. Some have just not had the BMS calibrated 100%. It's an easy fix and causes no harm.

 

That is always a possibility. But even still 18650 pack, Samsung 35E, 10s4p @14Ah nominal capacity. Arguably the wrong cell with 8Ah continuous discharge, total pack can handle 32A continuous, whereas the same pack with 30Q will be rated 60A. Perhaps this is a non-issue and the extra capacity will benefit range in lower power modes (Eco only draws around 6A)

I guess only time will tell on these 35E's... As of now, yes the best thing to do is drain the battery flat, which is 10% capacity leave the board off once it shuts off for 1-3 hours then recharge.

 

The batteries were tested side by side with 30q packs very early on in original testing of the prototypes leading to the GTR. The 35e pack consistently outperformed the 30q pack in tests. We have a write up we will be publishing soon which goes through the testing. The performance of the 30q in lower voltage is actually quite poor in comparison to the 35e. With the same voltage cut off as the GT, a 30Q and 35e pack actually return similar range. Once the voltage cut off was adjusted to suit the cell specs, the 35e surpassed it easily.
We still have 35e packs in use from 18months ago, and very early ones in use still in GT boards from before that.
Hope this helps,
Nick

 

That's actually good information to know! Thank you for sharing!

 

Not a problem. Once we have the write up completed, I will probably share it here.

 

Please do! I'd love to read it. Even more so if it's well detailed and loaded with specs! FYI I'm a nerd for such things lol

 

I tried to calibrate bms. I ran the board until dead(wouldn't power on). Then fully charged in 1 go. Went for a ride today and the battery still dies around 50-60%. The electonics were very hot to the touch through the casing. I'm waiting for evolve to work out shipping as i was quoted $300 ( couriers dont like Esk8 )

 

Hi
Yeah, unfortunately courier companies are becoming more and more strict with these. I'm sure they'll find a way to get it sorted for you.
Nick

 

Been over 3 weeks now and waiting since Tuesday for Evolve to reply.
Thought they would be interested in Battery sag as this board is specifically designed to not experience these issues. One of the main reasons i purchased a GTR.

 

After courier issues were sorted, board was sent to Evolve Hq for repair. Battery was faulty so now replaced. Issue seems to be sorted no drops in battery anymore....